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bobrk
You kids get offa my lawn
Premium
join:2000-02-02
San Jose, CA
Reviews:
·SONIC.NET

Bad upstream router?

Hey, I'm wondering if I can report bad upstream routers here. I ran the line quality test here at DSLReports, because my speeds seem to be off, and it reports a bad router at xo.net




Is there a way for you guys to lean on them and fix it?


bobrk
You kids get offa my lawn
Premium
join:2000-02-02
San Jose, CA
Reviews:
·SONIC.NET


NormanS
I gave her time to steal my mind away
Premium,MVM
join:2001-02-14
San Jose, CA
kudos:12
Reviews:
·SONIC.NET
·Pacific Bell - SBC
Do you see all of the routers between the highlighted XO Communications router and the destination? They are evidence the there is nothing wrong with the highlight XO router. That router is just programmed to ignore diagnostic packets.

Would you like my overly simplified description of "Trace Route"?

That said, if your speed is truly off, it will not be manifest by a bad upstream router. Speed problems are most likely caused by a fault, or three, in the loop between the DSLAM and the modem. So begin by posting your modem statistics during normal speed, and slowdown. Of interest are the SNR ("Signal to Noise Ratio"), sometimes labeled as, "Noise Margin" and Line Attenuation.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum


bobrk
You kids get offa my lawn
Premium
join:2000-02-02
San Jose, CA
Yeah, I understand the issues with traceroute. So what you're saying is that this tool that DSLReports supplies is not useful?

As far as the SNR stuff is concerned, perhaps I should contact support...


NormanS
I gave her time to steal my mind away
Premium,MVM
join:2001-02-14
San Jose, CA
kudos:12
Reviews:
·SONIC.NET
·Pacific Bell - SBC
said by bobrk:

So what you're saying is that this tool that DSLReports supplies is not useful?

I wouldn't say it is not useful. But it is easy to be misled if you don't have a grasp about how trace route works. As a hint, every trace route packet is dropped by every router in the route. The result depends upon the behavior of the routers.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum

iansltx

join:2007-02-19
Austin, TX
kudos:2
reply to bobrk
If the packet loss continued beyond that router, it would be an issue. It doesn't, so there's no issue.

Plus, the XO router is outside Sonic's network, so Sonic wouldn't be able to do anything about it anyway.


bobrk
You kids get offa my lawn
Premium
join:2000-02-02
San Jose, CA
I think the angle I was taking is that obviously Sonic has some kind of peer relationship with xo and could lean on them.

There is a greater chance that I don't understand the mechanism of how Sonic's networks are connected to xo's.


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET
XO Communications is a Telecom and Internet Backbone provider.

Equinix is a commercial Internet eXchange that facilitates peering between ISPs in multiple locations (two of which are in the Bay Area: San Jose and Palo Alto).

In your particular example the unresponsive router may actually be the XO-facing interface of the San Jose Equinix peering router.

Limiting(dropping) ping/icmp responses in a router is often an automatic response to heavy load to ensure that more important payload (tcp) gets delivered quickly. I agree with NormanS See Profile that the fact that there is no loss to routers on either site makes this a non-issue.
--
Got some spare cpu cycles ? Join Team Helix or Team Starfire!


bobrk
You kids get offa my lawn
Premium
join:2000-02-02
San Jose, CA
Reviews:
·SONIC.NET
Thanks all for your knowledgeable responses.

Is there any good use for this tool? What can be gleaned from its output?

Am I just seeing heavy entertainment traffic at night? I see from the ping monitors that my latency goes way up in the evenings.




leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET
said by bobrk:

Is there any good use for this tool? What can be gleaned from its output?

There is a lot of useful information in that output but it is not always easy to interpret the information. Depending on the nature of a network problem it can be misleading to rely on the test results from one end of the link without considering the reverse direction.

The things I look for are:
- packet loss
- spread between best and worst ping time
- increase in latency (fine for long distance legs, suspicious when between routers in close proximity)

As for the latency (ping time) in those latest charts, it is almost certainly due to the bandwidth utilization on your own DSL line. All you have to do is compare your results with those of other Sonic.net users (see the Line Monitor links).
--
Got some spare cpu cycles ? Join Team Helix or Team Starfire!